You won't be able to insure it in France unless you have a residence there.
You won't be able to insure it here if it's registered in France.
You'll need to show DVLA that it has been Exported from France.
You'll have to conform to the French transfer of ownership, whatever that is. If it's just sign a document you'll need part of it to submit to DVLA, who will then return it to France.

Import form pack from here;
http://www.dvla.gov.uk/onlineservice...ms.aspx?ext=dg
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